Here are a few quick search results in counter-chronological order for “illegal pharmaceuticals” (example search). Be aware that each platform works with a specific search approach and algorithm which is why we recommend for you to always compare and screen search results on more than one or two platforms:

Zenodo // zenodo.org

ScienceOpen // scienceopen.com

SciELO // search.scielo.org

Open Science Framework // osf.io

Open Knowledge Maps // openknowledgemaps.org

– https://openknowledgemaps.org/map/b84b42b4e5a281fd338c8202a55368d7 (on BASE) and
– https://openknowledgemaps.org/map/743a22448b50e97f4537ce91d8bf4596 (on PubMed)

Lens.org // lens.org

– https://www.lens.org/lens/search/scholar/list?q=illegal%20pharmaceuticals&preview=true

Figshare // figshare.com
– https://figshare.com/search?q=illegal+pharmaceuticals

DOAJ // doaj.org
– https://doaj.org/search/articles?ref=homepage-box&source=%7B%22query%22%3A%7B%22query_string%22%3A%7B%22query%22%3A%22illegal%20pharmaceuticals%22%2C%22default_operator%22%3A%22AND%22%7D%7D%7D

Dimensions.ai // app.dimensions.ai/discover/publication
– https://app.dimensions.ai/discover/publication?search_mode=content&search_text=illegal%20pharmaceuticals&search_type=kws&search_field=full_search

BASE Search // base-search.net
– https://www.base-search.net/Search/Results?lookfor=illegal+pharmaceuticals&name=&oaboost=1&newsearch=1&refid=dcbasen

Fine-tune your searches with other keywords, by language, region, author, date etc.
Should you hit a paywall, make use of the browser app Unpaywall.org or the Open Access Button.